Railway vehicle center bearing



Oct. 15, 1968 J. B. CUNNINGHAM 3,405,653

RAILWAY VEHICLE CENTER BEARING Filed May 18, 1966 FIG FIG-2 INVENTOR 3 JAMES B. CUNNINGHAM BY W ATTOR Y5 United States Patent 3,405,653 RAILWAY VEHICLE CENTER BEARING James B. Cunningham, Northwoods, M0., assignor to General Steel Industries, Inc., Granite City, 11]., a corporation of Delaware Filed May 18, 1966, Ser. No. 551,016 8 Claims. (Cl. 105-199) ABSTRACT OF THE DISCLOSURE A center bearing for supporting railway vehicle underframes, particularly of the floating center sill type, or swivel trucks comprising mating vertical axis pivot surfaces on the truck bolster and the underframe at the intersection of the body bolster and fixed center sill and wholly between the longitudinal side walls of the latter. For supporting vertical loads without loading the unsupported bottom wall of the underframe across the fixed center sill, at both sides of the pivot forming members the truck and body bolster are provided with opposing upwardly and downwardly facing horizontal bearing surfaces respectively, which are symmetrically disposed transversely with respect to the side wall of the fixed center sill. The opposing surfaces are normally symmetrical with each other longitudinally of the vehicle and the downwardly facing surfaces are longer than the upwardly facing surfaces and are preferably trapezoidal in plan so as to engage the upwardly facing surfaces throughout the range of truck swivel.

The invention relates to railway rolling stock and consists particularly in an improved center bearing construction for pivotally supporting a cushioned underframe of the floating center sill type on a truck.

In underframes of the floating sill type, in order to accommodate the passage through the bolster of the floating sill, the vertical webs of the bolster must be eliminated across the center sill, leaving only the top and bottom webs of the bolster in this critical region. This region, at the intersection of the bolster arms and the center sill, is critical because the bolster, loaded at its ends, is normally supported at its midpoint beneath the center sill by means of a centerplate formed on the bottom horizontal wall of the bolster, intermediate the side walls of the center sill. Since the thickness of this wall is limited by height limitations and it is impossible to reinforce the wall for the same reason, and since transverse vertical webs cannot extend across the center sill at this point, this part of the structure is extremely weak and liable to failure under the high loadings to which it is subjected.

It accordingly is a main object of the invention to provide a center bearing construction for cars of the floating sill type in which the vertical load is supported on the truck at points spaced transversely outwardly from the conventional centerplate location.

It is a further object of the invention to provide means for supporting a floating sill underframe on a car truck in which the supports for the vertical load underlie transversely spaced longitudinally extending vertical webs defining the side of the floating center sill opening through the bolsters.

A still further object is to provide a pivot support for a floating center sill underframe on a railway truck in which the vertical load supporting surfaces are each centered, transversely of the truck with respect to transversely spaced longitudinally extending vertical webs defining the sides of the floating sill opening through the bolster and the pivot forming surfaces of the center hearing are of substantially less diameter than the width of the center sill opening. 7

An additional object is to reduce the bending moment on the bolster by the increased transverse spacing of the load supports.

The foregoing and additional more detailed objects and advantages will be achieved by the construction described below and illustrated by the accompanying drawings in which:

FIG. 1 is a transverse vertical sectional view of a portion of an underframe and truck bolster structure embodying the invention, along lines 1--1 of FIGS. 2 and 3.

FIG. 2 is a bottom view of the underframe portion shown in FIG. 1.

FIG. 3 is a top view of the truck bolster shown in FIG. 1.

The underframe comprises a longitudinally extending center sill having a top wall 1, and vertical side walls 3 spaced apart transversely of the underframe and extending longitudinally thereof and formed along their lower margins with outwardly extending horizontal flanges 5. Near each of its ends the underframe is provided with a pair of transversely extending bolster arms aligned with each other transversely of the underframe and comprising a horizontal top wall 7 merging with center sill top wall 1, vertical side walls 9 spaced apart longitudinally of the underframe and extending transversely thereof and radi ally merging at their inner ends with side walls 3 of the center sill, bottom wall 11 extending horizontaly between the center sill side walls 3 and outwardly thereof a short distance, and there inclined upwardly toward the tips of the bolster arms. Bolster side walls 9 are interrupted between center sill side walls 3 to permit the passage therethrough of floating center sill S. Center sill side walls 3 are extended across the bolster arms by similarly transversely-spaced longitudinally-extending vertical webs 15. Intermediate side walls 9 the bolster arms are additionally reinforced by long central vertical webs 13 and short intermediate internal webs 14, all extending transversely outwardly from center sill side wall extension webs 15 and vertically between bolster bottom wall 11 and top wall 7. Instead of the usual centerplate, comprising a cylindrical boss depending from the center of the bottom wall and adapted to be pivotally seated in a mating recess in a truck bolster, bottom wall 11 is formed with a depending cylindrical wall 16 curved about an axis coincident with the intersection of the center sill and bolster arm center lines and of substantially smaller diameter than conventional centerplates.

The truck bolster 12 is of rectangular cross section having a substantially horizontal top wall 17 in the center of which is formed a depending vertical cylindrical wall 18 for pivotally receiving underframe cylindrical wall 16.

Truck bolster top wall 17, at each side of the recess formed by circular wall 18, is provided with flat upwardly facing rectangular surfaces 19 extending outwardly from the depression formed by wall 18 to points substantially an equal distance on the opposite sides of the center sill side wall extensions 15, and supports plates 21 of hard antifriction material such as hardened silicon bronze, the latter being retained against movement longitudinally and transversely of the bolster, i.e., longitudinally of the underframe, by rectangularly disposed upstanding shallow ribs 23, 25, 27 on the upper surface of the bolster along the transverse and longitudinal margins of the surfaces 19.

Horizontal flat downwardly facing pads 29' of isosceles trapezoidal shape in plan are formed on the bottom surface of the underframe bolster bottom wall 11, and are each symmetrical transversely of the underframe with center sill side wall extension webs 15. Pads 29 are machined and rest upon the upper surface of plates 21 so that the entire vertical load is supported a substantial distance from the center of the bolster and thus substantially closer to the outer ends of the bolster, thus greatly reducing the bending moment on the bolster as compared with a conventional structure. Since each pad 29 is centered transversely of the underframe with respect to a center sill side Wall extension web 15, the low resistance of the horizontal plate-like bottom wall to vertical loads is supplemented by much greater resistance of vertical webs and vertical side walls 9'to vertical loads. v

To minimize wear on the pivot forming surfaces 16 and 18 they are provided respectively with hardened steel liners 31 and 33. A horizontal wall 35 is formed along the bottom margin of truck bolster circular wall 18 at a lower level than the bottom of cylindrical wall 16 so as to avoid contact with the latter, and is provided at its center with centerpin hole 36. Spaced inwardly from cylindrical wall 16, an upstanding tube 37 is secured to the upper surface of wall 35, surrounding 36, to provide an annular recess in the truck bolster between cylindrical wall 35 and tube 37, which may be centerpin hole filled with oil, thus lubricating the region of frictional engagement between liners 31 and 33.

The small diameter of the mating pivot forming surfaces assures that there will not be substantial variation in frictional resistance to swivel resulting from the application thereto of horizontal forces such as the transverse forces resulting from centrifugal action while rounding curves, or longitudinal forces resulting from acceleration and deceleration of the car.

As will be evident from the drawings, the downwardly facing surfaces 29, 29 are as wide as upwardly facing surfaces of support plates 29, 29 and are substantially longer than and symmetrically disposed longitudinally of the vehicle with respect to the upwardly facing surfaces of support plates 21, 21.

The invention may be modified in various respects as will occur to those skilled in the art and the exclusive use of all modifications as come within the scope of the appended claims is contemplated.

What is claimed is:

1. In a railway vehicle, an underframe comprising a center sill having transversely spaced longitudinally extending side walls and a horizontal bottom wall connecting said side walls, a truck bolster having an upwardly facing top wall underlying said underframe bottom wall structure, mating pivot-forming surfaces formed on said bolster and said center sill bottom wall and curved about a common vertical axis at the center of said center sill, said pivot-forming surfaces being of substantially less diameter than the transverse distance between said center sill side walls, and pairs of opposing, frictionally engaging downwardly and upwardly facing surfaces respectively on said' center sill bottom wall and said bolster top wall, and extending transversely outwardly in both directions from the sides of said pivotforming surfaces substantially inboard of said center sill side walls to points substantially outboard of said center sill side walls, said downwardly facing surfaces being as wide as said upwardly facing surfaces but substantially longer than and normally symmetrically disposed longitudinally with respect to said upwardly facing surfaces.

2. In a railway vehicle according to 'claim 1, said downwardly facing surfaces at each side of said pivot-forming surfaces being symmetrically disposed transversely of the sill with respect to said sill side walls.

3. In a railway vehicle according to claim 1, said vertical pivot-forming surfaces on said center sill and said bolster depending from the bottom and top walls respectively thereof, the former being received within the latter.

4. In a railway vehicle structure according to claim 3, there being a bottom wall across the bottom of said truck bolster pivot-forming surface and forming therewith an upwardly open, downwardly closed recess in the top of said bolster.

5. In a railway vehicle structure according to claim 4, the bottom of said underframe pivot-forming'surface being open, there being a circular hole in the center of the bottom surface of said depression and a tubular member surrounding said hole and extending upwardly therefrom within said underframe pivot-forming surface, said tubular member permitting the passage therethrough of a centerpin while preventing loss of oil from the annular region surrounding said tubular member.

6. In a railway vehicle structure according to claim 1, one of said upwardly and downwardly facing surfaces being provided with a plate of hardened antifriction material.

7. In a railway vehicle structure according to claim 5, wear-resistant liners mounted respectively on opposing faces of said underframe and bolster pivot-forming surfaces.

8. In a railway vehicle structure according to claim 1, bolster arms extending outwardly from the sides of said center sill in substantial alignment with the center of said pivot-forming surfaces and comprising a top wall substantially coplanar with the top wall of said center sill, spaced apart side walls extending transversely of the vehicle and merging at their inner ends with the side wall of said center sill, and a bottom wall extending generally upwardly and outwardly from said center sill bottom Wall.

References Cited UNITED STATES PATENTS 1,806,075 5/1931 Martin -189 2,038,560 4/1936 Glaenzer et al. 105-189 X 2,119,062 5/1938 Stout et al. 105-226 2,833,227 5/1958 Heater et al 105-499 ARTHUR L. LA POINT, Primary Examiner.

H. BELTRAN, Assistant Examiner. 

